evalutate the double intergral

(double intergral sign) (2x2+y+1)dA

over the regionRdefined byx2<y<xand 0<x<1

much appreciated!

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- Jul 9th 2007, 08:37 AMturion645344double intergration 2
evalutate the double intergral

(double intergral sign) (2*x*2+y+1)dA

over the region*R*defined by*x*2<y<*x*and 0<x<1

much appreciated! - Jul 9th 2007, 08:51 AMThePerfectHacker
$\displaystyle \iint_R 2x^2 + y + 1 \ dA = \int_0^1 \int_{x^2}^x 2x^2 + y + 1 \ dy \ dx$

$\displaystyle \int_0^1 2x^2y+\frac{1}{2}y^2+y \big|_{x^2}^x dx$

$\displaystyle \int_0^1 2x^3 + \frac{1}{2}x^2+ x - 2x^4 - \frac{1}{2}x^4 - x^2 \ dx$

You can do it from there. - Jul 10th 2007, 04:24 AMturion645344
cheers, i then get $\displaystyle -2.5x^4 + 2x^3 - 0.5x^2 + x $ dx

which when intergrating between 1 and 0 gives

2.5 - 2 + 0.5 -1 = 0 - Jul 11th 2007, 07:47 AMturion645344
is then

2.5 - 2 + 0.5 -1 = 0

the right answer???

:D - Jul 11th 2007, 09:11 AMThePerfectHacker
I get 1/3